The North dome, powerful in presence, quietly occupies one of the most secluded areas of the Jami Mosque in Isfahan, Iran. In its silent presence, it narrates a story about an architecture that modestly glorifies both its creators, and in turn, their Creator, This structure is shaped by artists/architects who are not only 'builders', but also 'believers', constructing a building that spiritually serves as a house for God. Although its exact architectural function is unknown to us, its intellectual, artistic and spiritual message is clearly projected in each of its design features. In this paper, the underlying structural integrity and geometric principles in the North dome will be presented. On this basis, the construction of the North dome will be presented in relationship to the mosque complex, the social conditions and also the architectural characteristics of that period. Also, an overview of its unique structural traits and its mathematical relationships will be presented. Lastly, the geometric principles that are employed throughout the construction of the North dome and within its brick structure will be reviewed.